on the final stretch of putting up a 38x56 building with 14' wall height and starting to think about getting lights installed...
For the next year or two at least, the main part of the building will not have a ceiling (will finish out half of the building as a heated shop soon) and I'm looking to get the best bang for the buck in terms of lighting and coverage. With the height in mind, and of course cost, it seems that the 150w "security" lights would be a decent choice, maybe 3 per truss, which would span them across the 38' width, and the trusses are at 8' width. They seem to have a decent angle of coverage,
Define "decent angle of coverage", in this context. You didn't supply a link or any other means of determining exactly what fixtures you're talking about; but at least all other similar fixtures I've ever seen have been quite directional in practice. The 14-foot (or so) mounting height will help somewhat; but I'd still wager that you will need many more of these than you are currently assuming, in order to get good EVEN illumination down at working height. And realize too, that coverage is going to be asymmetrical, so the orientation of the lamps will also be significant.
and at 150w each, good beam strength.
If by "beam strength" you mean "brightness", you're apparently laboring under some serious misconceptions. Here is a typical Halogen bulb such as would be used in that type of fixture:
http://www.fastenal.com/web/products/detail.ex?sku=0724551
Note that it is rated at 2,400 lumens. Given the 150W consumption, that's only 16 lumens/watt -- pretty horrid; but set that part aside for the moment. Far more important (from your perspective) is the fact that even a single F32T8 fluorescent tube would actually provide MORE light; and presuming a properly designed (for that application) fixture, it will likely do a better job of putting that light everywhere you need it. At that point, the fact that it is doing all this on about 20% of the power can be viewed as simply a very nice bonus.
Anyone have experience using these in this situation? I don't want to light up the area above the truss chord as it's pretty expansive with a 6/12 pitch.
So put some reflectors above whatever fixtures you do wind up using. Or simply pick a fixture which already has such reflectors built in. I'm normally not a fan of so-called "High-Bay" fixtures; but in this case, a "moderate" one would be FAR superior to the lamps you're looking at. For example:
http://www.comfortmarket.com/eflt069.html
With four standard-issue F32T8 tubes, it would produce more than 11,000 lumens, on LESS power than your el-cheapo "security light"; and the photometrics would surely be better, too.
Halogen is just incandescent on steroids unless you have boatloads of money I would avoid it, the low price will be overshadowed by the power cost.
and the bulbs always seem to burn out too soon and are more costly then regular bulbs.
That's also true. And where he'd have to mount these fixtures, changing those bulbs would likely be a serious PITA.
as said I would go with t-8 fixtures. my personal preference is the 8ft fixture that tandems 4-4ft bulbs so u don't have to buy or handle 8ft bulbs.
Those MIGHT be usable in his application; but in general, I strongly prefer 4-foot fixtures. They're far more flexible in terms of both placement and switching/control.
If money is an issue.....you can pick up some of these...typically about $6/ea.....slap in a 23w CFL....put them where you want.....
I used a couple of them during the construction of my 2-story addition....
Having a couple of those around for temporary jury-rigged task lighting can be very handy. But as semi-permanent general lighting...? I don't think so.
The efficiency vs. initial cost decision will depend on how long the lights will be on.
High efficiency, high cost, fixtures make sense in a office or retail install where the lights are on 18 to 24 hours a day.
A casual use home garage or shop may only see 1 or 2 hours per weekday night and 3 or 4 on the week end.
A low cost, low efficiency fixture may make dollar sense in that case.
While that is true in theory, given the HUGE efficiency differences involved here it really would not take all that much usage to hit the break-even point.
Granted, $10/fixture for the halogens might seem like an insurmountable advantage at first blush. But by the time you figure that he'll probably need about 4-5 times as many of them (and correspondingly more "infrastructure" -- i.e., wiring, circuit breakers, electrical service capacity, etc. -- to support them), as compared to something like the fixture I cited above, that difference starts to shrink markedly. And I don't even want to think about what that $10 price tag implies in terms of long-term reliability.
appreciate the responses!
I do understand that they are not terribly efficient, but I have always appreciated the halogen portables that I have for their power, and that is pretty important here.
The other thing I need to keep in mind is that in Iowa it get's pretty cold in the winter, and even the -20 flourescents in my current garage seem to have problems in the winter.
Cold starting performance will be dependent not only on the tubes themselves, but also on the ballasts. If this is a major concern, you would do well to pay attention to that. There are even special fluroescent fixtures available which are expressly designed to be used inside walk-in freezers and such; and they work reliably at temperatures far below what you would typically encounter in your garage. HOWEVER... I suspect that you're over-thinking this whole issue: Presumably. you'll have SOME for of heat in there on the really cold days; or, if that garage is completely unheated, do you REALLY want to be working out there in sub-zero temperatures?
One other thought... You MIGHT want to use a minimal number of incandescent (or halogen, which as "Norcal" pointed out is essentially the same thing) fixtures for your "walk-through" lighting, so that you KNOW they will instantly come on, regardless of weather conditions. Then the bulk of the main lighting can be supplied by much more efficient means.
more than anything I want powerful light.
Then why settle for 2,400 lumens, when for the same power cost (and a lot less hassle), you can have 4-5 times that (or even much more, if you go with more ambitious "High Bay" fixtures, such as those which support 6-8 T5-HO tubes; but I really would not recommend that with only 14 feet of ceiling height to play with)?
In reality, what you REALLY need -- probably even more than raw brightness -- is evenly distributed light. If you keep that fact firmly in mind, your lighting scheme will sure be a much more successful in the long run.
